Is smoking marijuana more harmful than smoking cigarettes?
Unfortunately, the answer is not so simple. On one hand, it is true that marijuana tar contains about 50% higher concentration of chemicals linked to lung cancer, compared with tobacco tar, and that smoking marijuana deposits four times more tar in the lungs than smoking an equivalent amount of tobacco. This is because marijuana smokers hold the smoke in their lungs longer than tobacco smokers do, allowing more time for extra fine particles to be deposited in the lungs. As a result, the lungs of marijuana smokers show some of the same pre-cancerous changes as the lungs of tobacco smokers, and marijuana smokers suffer some of the same respiratory problems as cigarette smokers–i.e., chronic cough, bronchitis, etc. Despite this, the verdict is still out on whether smoking marijuana increases the risk of developing lung cancer later in life. In a way this paradoxical observation illustrates why it would be ill advised to rank different drugs with respect to their differential ability to c
